Sheet edging apparatus



l0 Sheets-Sheet 1 Filed May 4, 1950 7 ATTORNEYS y 2, 1953 G. WHITE SHEET EDGING APPARATUS Filed May 4, 1950 10 Sheets-Sheet 3 L 65c 90 250 229 252 r .10 Q0 69 m. i"wh' s l of I '10 85 100 101 A 96 {/35 62 l L 1 7 I 'm II 1 I I'm III 55 Ill I 79 63p 79 T iiiT 'FfiTr-Tb'fiT-iii 74 i! 80 60/ r v 69 INVENTOR.

ATTORNEYS y 12, 1953 G. WHITE SHEET EDGING APPARATUS 1O Sheets-Sheet 4 Filed May 4, 1950 mw fi m: m: n lllllllll IIRIIITFLNQI mmv J E 0 31 N8 091 z INVENTOR. -@dd% 5Z e za'flew -e ATTORNEYS May 12, 1953 G. WHITE SHEET EDGING APPARATUS l0 Sheets-Sheet 5 Filed May 4, 1950 v1. Li w? 7 14 0 ww z INVENTOR. B 52m @te zMle dfd .6

ATTORNEYS G. WHITE SHEET EDGING APPARATUS May 12, 1953 10 Sheets-Sheet 6 Filed May 4, 1950 INVENTOR. 2Z5Z (1 e Zaxffe -e ATTORNEYS y 2, 1953 G. WHITE SHEET EDCING APPARATUS 10 Sheets-Sheet 7 Filed May 4, 1950 Now I v H mom 3a a com mmu com 93 5 m 3m L .ll mmN l 0 f a 9.3 mu Q Q omu m 03 mu PM ma m w Id M May 12, 1953 6. WHITE 2,637,951

SHEET EDGING APPARATUS Filed May 4, 1950. l0 Sheets-Sheet 8 1 506 ,02 255 MO 1 242 E 512 a: o o c c o: o co Z60 zsa 259 245 260 246 264 265 Z56 Z65 ze4 V at? INVEN TOR.

zfmzd awe ATTORNEYS y 1953 G. WHITE SHEET EDGING APPARATUS l0 Sheets-Sheet 9 Filed May 4, 1950 y 1953 G. WHITE 2,637,951

SHEET EDGING APPARATUS Filed May 4, 1950 lo Sheets-Shet 1o 51a 2111 O l i i f a: 69

6 O 101 9 505 '1' 96 l 509 1 514 l 510 7 T o o i am 512 o i 515 I 51 I O 2,11 '11 3 15 o 316 ATTORNEYS,

Patented May 12, 1953 SHEET EDGING APPARATUS Gerald White, Rossford, Ohio, assignor to Libbey- Owens-Ford Glass Company, Toledo, Ohio, a

corporation of Ohio Application May 4, 1950, Serial No. 159,941

11 Claims. 1

The present invention relates broadly to the edge treating of sheets of plates of materials such as glass. More particularly, it has to do with a novel form of glass edging apparatus which employs a driven belt type of grinding or abrasive tool.

The invention is based on the discovery that by providing a readily flexible abrasive belt for this purpose, and by properly positioning the moving belt in, and diagonally of, the path of travel of the edge of a glass sheet to be treated, the flexible belt will, as the edge of the sheet moves into contact therewith, conform to and follow even an edge of surprisingly irregular longitudinal contour, to uniformly grind the same, from one end to the other; and further, that when two adjoining side edges of a sheet are successively moved past and in contact with a driven, flexible belt arranged in this manner to edge the same, the

moving belt will be found to have ground, not only the two side edges, but also the entire length of the edge areas of the corner portions which connect them.

It is therefore an important/aim of the invention to provide an improved form of belt grinder type edging device that is particularly well adapted for treating the edges of sheets and plates of large size and irregular outlinegand which is designed to grind the entire lengtho'f one side edge, and a portion of the lengths of both adjoining corner edge areas, in one pass of the sheet over the edging tool.

Another object is the provision of a complete edge treating apparatus employing a plurality of edge treating units of the above character that are arranged in a manner to rapidly and exe peditiously treat .the complete peripheral edge of a sheet or plate in an automatic-and substantially continuous manner. 2

Another object is to provide-in such an edging device, an improved means for supporting the flexible, abrasive belt in a manner, and in a location, that contact with the moving glass sheet to be edged will produce a flexing of the belt" to urge it into conformity ,with "the longitudinal contour of the adjacent glass edge, and with the leading and following corner edge areas thereof.

Another object'is the provision of a belt mount ing means of thischaracter which can be reversed and used interchangeably, at diiierent work points throughout a complete edge treating ap paratus, for positioning abrasive belts to grind either upper or lower longitudinal corners at either one of two opposite sides of a moving sheet. i

iii?

Another object is to provide a mounting of this kind that is movable toward and away from the work to be treated, and which permits swinging movement of the belt, in the plane of the work, to change'the angle at which the abrasive face of the unflexed portion of the belt is presented to the work.

Still another object is the provision of a complete edge treating apparatus of the above character wherein a sheet or plate of glass is supported and carried forwardly in a horizontal plane first into engagement with a series of belt type" grinding elements arranged in sequential alternate relation for grinding elements arranged in sequential alternate relation for grinding the upper and lower longitudinal corners of two opposite edges of said sheet, then shifted and again carried forwardly in a horizontal plane to engage a-second series of belt ty-pe grinding elements which are positioned to grind the upper and lower longitudinal corners of the remaining two side edges; and wherein the combined action of the two series of grinding elements will provide an overlap edge finish on the corner areas connecting the side edges of the glass sheet.

Other objects and advantages of the invention will become more apparent during the course of the following description, when taken in connection with the accompanying drawings.

In the drawings, wherein like numerals are employed to designate like parts throughout the same:

Fig. 1 is a top plan view of a complete glass edge treating apparatus embodying the features of the invention; 1 Fig, 2 is a fragmentary, diagrammatic, transverse sectional view through one margin of a glass sheet being operated upon by one of the belt type grinding'tools of the invention, showing two different angles at which the length of the working run of the belt can be arranged with relation to the plane of the glass;

- Fig; 3 is a fragmentary plan view of a side margin'of a glass sheet being edged according to this invention, showing the width of the working run ofthe belt arranged in, and diagonally of, the path of travel of the edge areas to betreated, and also showing the action of the flexible abrasivef belt as it'engages various areas along the side, and adjoining corner, edges of the sheet;

Fig. 4 is a perspective view of a cut sizeaof glass sheen-showing the difierent operative positions, with-relation to the sheet, of the-several belts usedin seaming glass sheets in accordance with the invention;

Fig. 5 is a perspective view of the skeleton framework upon which the operative elements of one section of the edge treating apparatus are mounted;

Fig. 6 is a fragmentary detail view of the glass supporting and conveying structure in the first edge treating section of the apparatus;

Fig. 7 is a vertical. longitudinal. detail view oi: the supporting structure, taken substantially on line 7'i of Fi 6;

Fig. 8 is a side elevation of one of the edge treating units of the apparatus, taken substan--- tially along the line 8-8 of Fig. 1;

Fig. 9 is a vertical transversesectiolr through the locking device for the carrier cradle of one w of the edge finishing units, taken substantially on the line fi9 of Fig. 8;

Fig. 10 is a vertical transverse section through the pressure control devices for restricting the swinging movement of the motor from the edge finishing unit, taken substantially along the line ill-40 of Fig. 83

Fig. 11 is a top View of the edgetreating unit of Fig. 8;

Fig. 12 is a vertical transverse section: taken on line iii-i2 of Fig; 11;

Fig. 13 is a vertical, transverse section taken on'li'ne l3-l3 of Fig. 11 and showing the belt tensioning device;

Fig. 14 is a side elevation of a form of pressure roller used throughout the supporting and. con veying structure;

Fig. 15 is a fragmentary side elevation of one section of the edge treating apparatus onan enlarged scale;

Fig. 16 is an end view ofthe transfer section of the apparatus, showing its position relative to the edge finishing sections thereof;

Fig. 1'7 is a fragmentary, detailsectional view of the transfer unit taken substantially on line I'I-I'i of Fig. 16;

Fig. 18 is a diagrammatic view of the control system for operating the transfer unit;

Fig. 19 is a side elevation of the transfer unit and the front end of the second edge finishing section of the apparatus;

Fig. 20 is a fragmentary top view of the transfer unit, illustrating the several drives employed therein;

Fig. 21 is a top plan view of the second edge treating section of the apparatus;

Fig. 22 is a side elevation of the second edge treating section;

Fig. 23 is a fragmentary detail view of the glass supporting and conveying structure in the second edge treating section of the apparatus; and

Fig. 24 is a vertical longitudinal detail view of the supporting structure shown in Fig. 23.

Referring now more particularly to the drawings, there has been shown in Fig. l a plan view of one preferred form of complete edging apparatus embodying the features of this invention. As there shown, the apparatus includes afirst conveyor section A, and a second conveyor section 13 arranged at right angles to the first conveyor section. Both of these conveyor sections are adapted to support glass sheets in a horizontal plane, and to carry them forwardly in a substantially straight line from one end to the other; and mounted along either side of the conveyor sections A and B are edge treating units 0 which are adapted to grind or finish opposite edges of the glass plates as they move along the conveyor sections A and B,

With this arrangement, a plate 25 to be edge treated is placed on a loading conveyor D, lo cated in advance of the first conveyor section A, and is moved thereby onto the first conveyor section. During travel over the conveyor section A, the two opposite short edges 25 and 2! of the sheet 25 will be appropriately treated by the adjacent edging units C, and will be in finished form by the time the sheet 25' passes from the conveyor section A onto the transfer section E which lies between the exit end of the section A and the-entrance end of the section B. On the transfer section E the direction of travel oi the sheet 2'5 will be shifted degrees, in a manner to be more clearly hereinafter described, to feed it onto the section B and to present the two opposite long. edges 28 and 29 to the edge treating units C associated with this second conveyor section.

As a consequence of this substantially continuous procaim'e, when the sheet Z5 reaches the end of the: conveyor section B and is: received upon the discharge conveyor F, all four edges of the sheet. 2.5 will; have been edged.

As indicated above, and shown diagrammatically in Fig. 2, the actual edging tool of this invention is. preferably in the form of an endless belt 30. The belt may be of canvas or other tough, flexible material, trained about a pair of. spaced pulleys 3i: and 32' to provide a working run 33 and a. return run 34, and has its outside surface 35 coated with a suitable abrasive.

Abrasive belts of this general character have previously been used to grind the edges of glass sheets and it is customary to effect the grinding action by bringing an edge of a glass sheet to be ground into grinding engagement with the working run of the belt. To this end, the belt is'positioned with the length of its working run arranged at an angle to the plane of the sheet to be edged, and the angle chosen is decided by the type of edge finish to be produced.

For example, with the length of the working run 33 at an angle such as is shown in full lines in Fig. 2, the upper longitudinal corner 3% of a glass sheet 25 will be ground off to produce a beveled, or part of a seamed, edge. A similar result will be obtained when the length of the working run 33 is positioned at the angle shown by the broken lines in Fig. 2, except that the lower longitudinal corner 31 of the sheet will be ground off. On the other hand, a square corner can be produced by arranging the length of the work run 33 at right angles to the plane of the sheet 25 being ground, and various other edge finishes can be obtained by suitable alteration in the angle made by the length of the working run of the belt with the plane of the sheet.

Now all of these various edge shapes can be produced and/or finished by the apparatus of the present invention. But what is more important, they can be produced on edges of curved or irregular, longitudinal contour, as well as on straight edges and, in addition, corner edge areas, connecting the edge being ground with the two adjoining edges of the sheet, can also be treated at the same time and as part of the same operation.

As best illustrated in Fig. 3, this is accomplished, regardless of the angle of the length of the working run 33 with the plane of the sheet, first by positioning the working run 33 of the belt 36 in the path of travel of the edge area to be treated and, second, by arranging the width of the working run 33 of the belt diagonally of the pathof 5, travel of this edge area and with the abrasive surface 35 of the belt at an acute angle to the edge to be treated.

With this arrangement, as the sheet moves in the direction of th arrow, the angled Width of the working run 33 of the belt will be contacted first by the curved corner edge area 38, causin the flexible working run of the belt to conform to the contour of the corner edge area during grinding as shown at 39, and this will be true regardless of whether the corner is curved (as shown) or sharp. Then, as the sheet 25 moves on, the working run of the belt will progressively contact and grind the entire side edge of the sheet as illustrated at 4!. During this time, the thrust of the glass sheet against the working run of the belt flexes or twists the glass contacting portion thereof into the position shown at H where it is substantially parallel with the edge being ground. At the same time, the tendency of thi portion of the belt to return to its normal or diagonal position relative to the glass edge (as indicated in broken lines at Ma) will maintain it in intimate contact therewith and insure full grinding action, regardless of whether the belt is acting on an edge that is of straight, curved or otherwise irregular longitudinal contour. This same tendency of the width of the Working run of the belt to regain its normally angled position, will cause it to maintain it engagement with the following corner 42 of the sheet, as shown at it and M, to grind the same, as the end of the sheet approaches and moves past the working run of the belt.

As pointed out above, the abrasive belt grinding tool of the invention when properly mounted and positioned will operate in the manner just described to produce and/ or finish both longitudinal side and corner edge areas of the desired type, even on unusually large or irregularly sized s and shaped sheets, regardless of the angl at which the length of the working run 33 of the belt til is held to the plane of the sheet.

The invention has, to date, had its greatest commercial success when used in connection with the seaming of the edges of glass shets, and it will be specifically described in that connection here.

The term seaming is used in the glass art to describe a type of edge finish, usually given to cut sizes of glass, and in which the top and bottom longitudinal edge corners of the sheet are ground down to remove the objectionable sharp edges. In the particular embodiment of the invention shown in the drawings, the belt grinding tools carried by the edge treating units C are so positioned and arranged relative to the path of travel of a glass sheet through the complete edging device shown in plan view in Fig. 1 that when a glass sheet has completed its travel over the conveyor section A and B and has been discharged onto the conveyor F the entire perimeter of the sheet will have been properly seamed.

Thus, the abrasive belts 3!] in units 45 and 46,

of the edge treating units C that are associated with the first conveyor section A, have the length of their working runs 33 angled with respect to the plane of a glass sheet on the conveyor as shown at ll in Fig. 2 and at 48 in Fig. 4, to grind the upper longitudinal corner 35 of the short side 25 of said sheet. The working run of the belts associated with units 49 and 5B are angled as shown at ill in Fig. 4, to grind the upper longitudinal corner 36 of the opposite short side 21 of the sheet; the working runs of the belts of units 1 6 52 and 53 are angled as shown at 54 in Figs. 2 and at 55 in Fig. 4, to grind the lower longitudinal corner 31 of the short side 26 of the glass sheet; and the working runs of the belts of the units 55 and 51 are angled as shown at 58 in Fig. 4, to grind the lower longitudinal corner 3'! of the opposite short side 21.

At the same time, the width of the working runs of the abrasive belts of all these edge treating units are located in the path of travel of the edge area and diagonally thereof as shown in Fig. 3, so that each belt will grind not only a side edge of the glass sheet but also a portion of the corner edge area at either end thereof.

The belts 30 may be faced with abrasive of any desired grade to giv either a rough or a fine grind. Or, where, as in the present embodiment, a plurality of belts operate on the same edge area, the first of these may be a coarse or cutting abrasive tool and the final ones a fine or finishing tool.

The edge treating units C that are associated with the second conveyor section B are duplicates. both in structure and arrangement of abrasive belts, of those associated with the first conveyor section A, and so will edge treat the opposite long side edges 28 and 29 of a glass sheet 25 passing along the conveyor section B in the same manner as the short side edges 25 and 27 have been treated on the conveyor section A. As a result, when a glass sheet has been conveyed in one direction along the conveyor section A and then in a direction at right angles thereto along the conveyor section B, the entire perimeter of the sheet will have been seamed by the edge treating devices C.

With regard now to the detailed construction of the complete edging apparatus shown in Fig. 1. the loading conveyor D, upon which glass sheets 25 are received and passed to the conveyor section A of the complete edging apparatus, may be of the conventional endless belt type and driven by a chain and sprocket connection '59 from a suitable source of power 65.

The conveyor section A, upon which the two opposite side edges 2e and El of the glass sheets 25 are to be treated, comprises a driven roll type conveyor 62 in horizontal alignment with the loading conveyor D, and a series of transversely arranged, alternately reversed framing structures 53 for supporting the conveyor 52 and the edge treating units C that are associated with this conveyor section.

As shown in Figs. 1 and 5, each of the framing structures 63 is in the form of a generally rectangular framework made up of a pair of vertical columns or standards (it and 65 connected together at their upper ends by the horizontal channels 56 and adjacent their lower ends by the similar channels 61. Spaced from the standard 65 of each framing structure 63 a distance sufiicient to accommodate the roller conveyor 62 is an auxiliary vertical standard 68 which is also secured to the channels 65 and 67 as best shown in Fig 5.

Alternate framing structures 63 are arranged in reversed and staggered relationship to, and spaced from, one another so that the vertical standard 64 of each framing structure is in line with the auxiliary standard 63 of the framing structure on either side. With this arrangement, the major portions of alternate framing structures 53, terminating in the vertical standards 65, will extend outwardly at opposite sides of the conveyor section A for mounting the edge treating units 45, 46, 29 and 55 in a manner to be more clearly hereinafter described; and the rectangular frames bounded by the vertical standards 8t and 68 and the horizontal channels Eli and 6? of each framing section will be in horizontal alignment in order to accommodate and support the roller conveyor 62 extending therethrough.

For this purpose, there is secured to the vertical standards E l and {it of each framin structure, between the horizontal channels b and El, a bridging beam (3, and these bridging beams carry the pairs of side rails 39 ill and ll, '52 of the roller conveyor '32 (Figs. 1, 5 and 6). It will be noted that the pairs of side rails 69, iii and Ti, lF: consist of a plurality of longitudinally spaced sections an that the sections of the pair 69 and Ill on one side of the conveyor are staggered relative to the sections of the pair ll and "E2 on the opposite side of the conveyor so that each bridging beam 'l'o carries the forward ends of the rails of a section of one pair of side rails and the rearward ends of therails of asection of the other pair of side rails. In this way, the spaces between the side rail sections will. form staggered open areaways '54 in opposite sides of the conveyor 62 to permit the location of edge treating units C in position to operate upon the glass sheets on the conveyor as they pass these points.

At the entry or receiving end of the conveyor section A, the outer side rail oil of the roller conveyor 52 is extended forwardly beyond the first bridging beam '13, as at 69, and a supplementary section '52 of the opposite outside side rail T2 is secured to and also extends forwardly from the beam is a corresponding distance, to carry the initial rolls E5 of the roller conveyor 62.

All of the rolls of the conveyor 62 are preferably made up or" a bod portion it of suitable material such as rubber which is vulcanized. or otherwise secured to a shaft 'i'i, and the shafts of the initial rolls F5 are journaled in bearings mounted on the extensions or continuations 69' and 72' of the outside rails and E2 or" the conveyor. The initial rolls iii are all of the same length and are mounted in the same way as the rolls '55 which are located, and adapted to support and convey glass sheets, between the open area ways Hi; the opposite ends of the shafts ll of the rolls l9 being journaled in bearings 8t mounted on the outside rails Gil and 12.

However, within the open areaways it, it is necessary to employ conveyor rolls of different lengths, and mounted in a somewhat different manner, in order to support a glass sheet carried thereby on one side and to expose the other side of the sheet to the action of the edge treating units C which are movably operable within these areaways. Thus, as will be noted in Fig. 6, there is provided in each of these areaways M a short central roll 8i and two flanking rolls 32 and 83 of intermediate length. All of these central and flanking rolls that serve the areaways M on one side of the conveyor 52 are supported from one end only, by having that end of their respective shafts Tl journaled in bearing 84 and 85 mounted on the pair of side rails 69 and 76 respectively. Similarly, those central and flanking rolls that serve the areaways on the opposite side of the conveyor are also mounted from one end only by having an end of their shafts Tl journaled in similar bearings 86 and 35 carried by the opposite pair of side rails H and T2.

The rolls l5, 19, 8|, 82 and 83 throughout the section A of the edge treating apparatus are driven in common from a centrally located power unit 8'1, as shown in Figs. 1 and 15, by means of a progression of link belts as trained about double sprockets 89 and so carried on the ends of the roll shafts Tl in the closed end of each areaway ls. The belts 8 8 are arranged, as is shown in Fig. 6, to couple pairs of shafts in driving relation by being trained about adjoining pairs of sprockets 3G and, alternately adjoining pairs of sprockets The power unit 8? is operatively connected to one shaft l1, indicated at 9| as the power take-off, by a link belt 92 trained about a sprocket d3 of said shaft and a similar sprocket on the shaft of the power unit. This shaft 9|, as well. as the shafts l? of the other rolls '19, as will be noted in Fig. 6, has sprockets 89 keyed thereon at both of its ends so that the progression of link belts 88 will drive the plurality of rolls located forwardly and also rearwardly of the said shaft. More particularly, from the power take-off shaft ill, the progression of link belts 88 will carry driving power to the entry end of the section A through the belt series indicated at 88c, then at the last full length roll 79 will transfer the drive across the area of the conveyor 62 to the series of belts 882) which will again transfer the drive to a series of link belts located similarly to the belt series 83a. Likewise from the opposite end of the takeoff shalt Ell, the sprocket 89 secured thereon will drive the belt series 880 to carry the driving power rearwardly through the section A in a similar alternating manner.

To urge the sheets downwardly onto the rolls of the conveyor t2 and more particularly restrain them from shiftin laterally during the edging action of the abrasive belts of the edge treating units C, a series of spring pressed rollers (Fig. 7 are supported above the glass sheet and caused to elastically press downwardly upon the same. These rollers are each rotatably mounted by their internally journaled shaft to on angle bars :35, connection being made thereto by a nut 9'! on the threaded end 93 of said shaft, as shown in Fig. I l. The angle bars Elli are provided at each end with vertically disposed roc 99 that extend through slotted openings I83 of a plurality of bars it! carried by, as shown in Figs. 6 and 7, and secured to the top and bottom surfaces of the upper horizontal channe1 66 in the first portion of the section A.

Each rod 99 has an integral collar portion I02, said collar supporting one end of a spring [03 that bears at its opposite and against the lower bar Elli. The normal energy of the springs I03 located at each end of an angle bar 96 is to urge the same downy-var ly and consequently position the rollers El i against the rolls of the conveyor o the sheet of glass 25 moving thereon. The angle bars 516, similarly to the side rails 65 iii, '1! and it, previously described, are alternately arranged according to the open areaways M and to exert a downward thrust, by the springs "13, on that area of the glass sheet 25 supported on the short rolls 8E, 32 and 83 and intermediate full length rolls 79 while the edge of the unsupported area is being actively engaged by the belt 30 of the adjacent edge treating unit C.

As best shown in Fig. 8, the horizontal channels (i6 and 6? of the framing structures 63 provide a support for the edge treating units C. Each of these units C comprises a carrier cradle or carriage Hi l, a. motor support frame hi5, and a belt support arm H36 mounted thereon. These associated members of the edging units are suitably forn'ied, and provision is made herein, so

,that their relative positions of association may be reversed and, without modification, they will be adaptable to function according to the desired positions of the edging units throughout the edge treating apparatus as shown in Figs. 1, 8 and 15, or Figs. 21 and 22. For example, the motor frame I05 may be inverted from a position shown in Fig. 8 to a position such as is shown in Fig. 15, depending on whether the edge treating unit C" is to be bodily located in a position generally above or below the horizontal .path of travel of the glass sheets on rolls of the conveyor '52. Likewise, the belt supporting arm I06 of each unit C is adapted to be mounted on the related motor frame I05 so as to extend substantially into the path of the glass sheets so as to locate the abrasive belt 30, in contactual relation to either the upper or lower longitudinal corner of said glass sheet as shown inFig. 4. The supporting arm 100 is thus locatable with respect to the motor frame so as to be disposed in a substantially upward direction when the carriage I04 in general is disposed below the plane of the conveyor rolls, as shown in Fig. 8; or to be located in a generally downward direction therefrom when said cradle is disposed above the plane of .the conveyor rolls, as will be noted in Fig. 15. As will be set forth more in detail hereinafter, the supporting arm I is also finished on its opposite surfaces to provide for mounting of said arm on either side of the path of the glass sheets as they are carried on the rolls of the conveyor 62 and is thus adaptable to association with the motor frame I so that it will always be directed inwardly toward the said rolls.

The foregoing general description is believed to set forth the novel construction of the edge treating units C; namely that, according to the disposition of the carriage I04, the motor frame I00 is adapted to positional relation in at least two manners of construction while the supportof relationship whereby the abrasive belts 30 will be directed against the designated corner of a glass sheet and according to the side of the said sheet to be treated.

The carrier cradle or carriage I04 is supported for movement between the horizontal channels 8% and 8'! which are provided with directive track elements adapted to carry said frame in a substantially horizontal plane and also sustain the same in a substantially vertical position. More particularly, the carriage I04 has a generally open rectangular form having a web that is T-shape in cross section and including a top web section I01, bottom web I08 and side web sections I08. The side web sections I09 are formed in their lower portions to provide outwardly directed flanges I I0 in which are journaled the axles III of wheels H2. The wheels II2 support the carrier cradle I04 in rolling contact on a vertically projecting rail II3 mounted on the web II4 of the lower horizontal channel 61 and secured thereon between angles II5. Preferably, the rail 5 I3 is secured by bolts IIB between the upstanding legs II? of said angles II5 while the horizontally disposed legs I I8 thereof are fixedly se-.

cured to the web II4 of channel 01 by bolts II9,

. substantially as is shown in Figs. 8 and 12.

.the rail II3 by means of a plurality of rollers I20 that are carried on vertically disposed shafts I2I journaled in bosses I22 integrally formed in the bottom web section I08 of the cradle. If desired, the shafts I2I may be eccentrically located with referenc to the axes of the rollers I20 so that said shafts can be revolved within the bosses I22 to compensate for misalignment or wear, in a manner well known in the art. The rollers I20 are disposed on opposite sides of the bottom web I08 of the carriage I00 and cooperate with series of rollers I23 disposed along the upper web I07 to maintain the said cradle in a freely movable, vertical position. More particularly, the rollers I23 are journaled on shafts I24 threadably secured in bosses I25 formed on the upper section Illl of the web of the cradle as shown in Figs. 8 and 11. The rollers I23 are located in the opposite upper corner areas of the carriage and their peripheries engage bars I20 and I21 which constitute side rails secured in spaced relation to the under surface of the web i28 of the upper horizontal channel 06. Intermediate the rollers I23 and generally in a central location on the upper web section I01 of the carriage I04 there is also a roller I29 journaled on a shaft I30 carried in ears I3 I which roller rides on the under surface of the channel web i213 and acts in an auxiliary sense to prevent the cradle from becoming vertically displaced from the rail H3.

The carriage I04 is movable along the rail II3 to provide for such lateral adjustments as may become necessary to accommodate glass sheets having different widths and/or lengths. Obviously a variety of dimensional sizes are not passed at random or without selection through the apparatus and lateral adjustment of the carriages I04 in either of the sections A or B is preferably made before a production run of one particular size of sheet. For this purpose, the rail H3 is provided with a series of slotted openings I32 which may be regularly spaced along its body portion as is shown in Fig. 8. Each of the carriages I04 is secured in any of the positions to which it may be adjusted, by means of bolt and nut connections I33 that are passed through openings I34 in a plate I35, carried by the carriage, and the openings I32 of the rail H3. The plate I35 is attached to the lower web I08 of said carriage by bolts I30 as may be seen in Fig. 9. The carriages I04, disposed along the path of travel of the glass sheets and alternately on opposite sides thereof, may each be accordingly shifted laterally inwardly or outwardly to properly position the abrasive belt of their related unit C according to an increase or decrease in the width or length of the glass sheets to be edge treated.

The motor frame I05 is pivotally carried within the carriage I04 so that it is swingable about a vertically disposed axis. For this purpose, as will be seen in Figs. 8 and 12, the T-sectional web of said carriage is enlarged to provide pads I 31 and I38 in the medial area of its upper and lower sections I0! and I08 respectively. On the pads I31 and I38 are mounted bearings I30 and I00 in which are journaled stub axles Hit and M2 of the motor frame I05. The stub stafts MI and I42 are received and secured in bosses I43 integrally formed in vertically axial relation in the web I44 of the frame. More particularly, the frame I05 has a generally rectangular outline described by the L-section web 40 which includes a top web section I05, bottom web section I40 and vertical side web sections f ll.

At the corners formed by the several sections of the web there are outwardly pro ecting upper and lower web sections I48 and M9, respectively, thatterminate in and support a mounting panel I 50 fer the support arm I06, As shown in Fig. 12, the'mounting panel I50 is inclined to the vertical plane so that the arm I95 will be disposed at an angle of substantially 75 degrees, and, while this angle is stated as an example, the panel may be located at other desired angles according to the best presentation of the abrasive belt to the work.

The motor frame I05 is generally swingable about the vertical axis afforded by the stub axles I 4I and I42; however, it is preferable to restrict this axial mbv'eihent to maintain the belt 30 while in grinding or abradi'ng' engagement with the glass so that it will be caused to seem the immediate area of its engagement, or the working run, fion'i the normal continuity of its travel and to estimate this restriction biily to direct the belt strain it in one postman and at the same timealloii'r its axial motion in at least one direction should the tension ih the belt set up 'a thrust on the glass that is excessive to that pressure desired in the area of grihdii Asherein forth, will be noted in Figs. 3

shit '10, the frame 1051s broviiied with arms is! and I52 projecting biitwardly from the side webs 141. Preferably, the arfrl IE2 is located from the top web its a distance that is ed'u'al to the 100atibh bf the arm I51 from the bottom web I46 in girder that it will be similarly positioned when the time I85 is inverted-as p evitusiy set fo'rth. According to one position of the frame 165, such as that shbwh in Figs. 8 and 10, theextremity of the arm I51 is lh'ca't'ed between resiliently acting element's gehje'r'auy desigh'ate'd I53 and ms; one being adaptedto vary the nbri'nal phsition bf the frame I05 while the other element is capable of tel-slitting anal motion or ssm rsme to reduce develbping t'ehsion in the belt '30. The elements as and 'isajaie bodily harried on a bracket 1'55 that is hiredly secured to side web F of the barrage I'M by in'eah's o'f a bifurcated end I56. Outfit!a l dl'y from the end 155, the brabket I55 has a mam-tea arm portion I51. At the outer ei'id of the reehforced portion "I51, there are formed at substaht'ially right angles thereto outtar-my ahd 'upwardI'y formed arm I58 and I59. The arm I58 is adapted to carry the resiliently acting 'elemeht I53 while the element I54 is carri'e'd by the arm I59.

The element I53, as shown in Fig. 10, comprises a rod 'IBil having an enlarged head I61 at one eh'djthereof and having the opposite end threaded as at I62. The rod I '60 is bodily and slidably car- 'ried in a sleeve I-B3 formed as a part ofthe arm I 58. Between the emer ed head 151 and the adjacent end of the arm I 58, there is interposed an expansion type spring I54 which normally'exerts its pressure against the head I'GI to urge the same against the arm 15| but this spring characteristic is restricted by lock huts I65 threaded ontothe end 162 of the rod I50 extending outwardly from the sleeve I53. By adjusting the positions of the lock nuts I 65 along the threaded end I52, the expansibility of the spring I64 can be regulated and the amount of extension of the rod thus be controlled when the desired normal position of the motor frame is once ascertained.

The element I54 is carried on the arm I59 of 12 bracket I55 and is provided in the form of a fluid responsive cylinder I56 and piston I61 contained therein. The outer head I08 of the rod I69 for piston I61 is disposed in engagement with the arm It I in opposition to the head IBI of rod I60. The piston I6: is under constant pressure to urge the rod I89 outwardly and this pressure is supplied from a reservoir I10 also carried on the arm I59. The reservoir I10 is provided with an adjustable, spring loaded piston I1I which will maintain a constant head pressure in the cylinder I68, and consequently the end 108 of piston rod M59 in conta'ct with the arm IEI of the motor frame I05.

Thus, when the desired angle of engagement of the belt 30 has been established with reference to the edge of the particular size or contour of glass sheet to be ground, the nuts I65 are adjusted along the threaded end I62 of the rod I60 until the expansion of the spring I64 and the pressure within cylinder I66 are balanced or equalized. Now, if the thrust imposed by the glass sheet on the belt 30 in its working run exceeds the normally desired tension, the reacting force will cause the motor frame I to pivot on the stub axles I41 and I42, causing the arm 'I5I to press against the head I68 01 the piston rod 59 and temporarily overcome the predetermined pressure within the cylinder I66 to urge the iston I 611 therein inwardly and the contained fluid into the reservoir Iili. When this pressure condition is reduced or corrected, the piston I H of cylinder 515 is caused by its spring load to return the fluid to the cylinder I86 and force the piston rod I69 outwardly thereof until the arm I5I is again brought into contact with the head IBI of the spring governed rod I60.

The support arm I08 of the edge treating unit assembly has a generally arched or curved outline that is followed throughout the H-shape cross section I12 of its body portion. At the ends of the arm, this particular cross section I12 is flared outwardly to form bifurcated ends or yokes I13 and I14. As shown in Fig. 12, one end of the support arm, as by the yoke I13, is fixedly positioned against the mounting panel I50 and is provided in its side walls I15 with openings I through which securing bolts I11 are threaded into said panel.

Preferably, the outer surfaces I18 of each side wall I are suitably finished for mounting the I06 against panel IEE, as previously described, so that the said support arm can be located in any of the positions as shown in Figs. 8, 11., 15, 21 and 22, and so as to project inwardly with respect to the openareaways 14 from the motor frame I on the opposite sides of the roll conveyor 62 since the edging units are located in alternate relation on the opposite sides of the apparatus. Also, the bolt openings I16 in the side walls I15 are also arranged to register with the complementary threaded openings I19 in the panel 150 when the arm I95 is positioned to extend upwardly or downwardly as particularly shown in Figs. 8 and '15.

The side walls I15 of the arm yoke I13 are also formed with suitable openings I89 to receive a Journal bearing I8! for a shaft I82 on which a drive pulley 183 for the abrasive belt is securingly mounted, said bearing IBI being secured within a recess I84 formed in the body of the panel I of the frame H35. The shaft I82 is operatively connected to a motor I85 that is mounted on a ledge I86. The ledge isintegrally formed with the bottom web section MS of the frame I05 and has a platform surface I81-'dis'posedat sub- 13 stantially right angles to the mounting panel I59 in order that the pulley I83 and motor I85 will be located in axial alignment and substantially at right angles to the major axis of the vertically inclined arm I96.

In the yoke I14 at the opposite end of the arm I96, a belt supporting pulley I88 is located between the side walls I89 thereof and mounted on the journaled shaft I99. Trained about the pulleys I83 and I88 and a tension idler pulley I9I is the continuous abrasive grinding belt 30. (To coordinate the earlier description of the belt 39 with the immediate detailed description, it is here pointed out that the pulleys I83 and I88 were previously and broadly mentioned as the pair of spaced pulleys 3| and 32, in connection with Fig. 2 of the drawings.)

The idler pulley I 9| is rotatably carried on the support arm I96 by means of a double arm yoke member I92 that normally is sustained in an outwardly directed, tension-creating position by means of a pair of springs I93 as best seen in Figs. 8, 11 and 13. The yoke member I92, as best seen in Fig. 13, is pivotally carried on the supporting arm I96 by means of a shaft I94 that is secured in an integral boss formation I95 of the arm by a set screw I96. The opposed outer ends I9'I of shaft I94 are located in trunnions I98 formed in the leg portions I99 of the yoke member I92.

The legs I99 project from centrally formed bosses 299, that are interconnected by a web MI, and from which extend in the opposite direction the leg portions 292. The outer ends 293 of said legs 292 are provided with openings for receiving and supporting a threaded shaft 204 on which are mounted bearings 295 for the idler pulley I9I and which are received in recesses 296 in the end walls 29! thereof. To secure the shaft 294 within the legs 292, the same is provided with a head 298 which is drawn against one leg by means of a nut 299 threaded thereon and against the opposed leg 292.

The centrally disposed bosses 209 of the yoke I92 are provided with suitable openings to receive shafts 2 I9 integrally formed with blocks 2| I. The blocks are retained in surface bearing relation with the outer surfaces of the bosses 209 by cotter pins 2I2 inserted through the outer ends of the shafts 2|9 and bearing against suitable washers 2| 3. The blocks ZII are cross drilled as at 2I4 to slidably support rods 2|5 upon which the springs I93 are loosely carried.

The rods 2I5 are pivotally supported at their opposite ends on arms 2I6 (Fig. 11). The arms 2 I6 are fixedly mounted on a common shaft 2" that is journaled in a transverse boss 2| 8 formed in the H-section I'I2 of the arm I96 and preferably one of said arms 2I6 is formed to have a diametrically projecting portion for providing a crank 2I9, having a handle 229, for manually actuating the arms 2I6 and thereby the rods 2| 5. The ends of the rods 2|5 are secured in substantially square members 22| that are pivotally supported on the arms 2| 6 by pins 222. The springs I93 being located between the blocks 2 and square end members 22I of the rods 2| will thus be compressed when the members 22I are carried toward the blocks 2| I thereby urging the tension pulley I9| into a tension creating position with reference to the grinding belt 39 and as the yoke member I92 is swung on its supporting shaft I94. In this manner, when the arms 2I6 are rotated by the crank 2| 9 in one direction or clockwise with reference to the blocks 2 and reduce the supporting roll conveyor 62.

action of the springs I 93 and consequently relieve the tension of the belt 39. When rotated in a counter-clockwise direction, the arms 2I6 will carry the rods 2I5 forwardly toward the blocks 2 and will set up a tension in said belt as the springs I93 bear against the side blocks, and urge the yoke member I92 outwardly.

Th edge treating units are thus composed of three generally basic members; namely, the carrier cradle or carriage I94, the motor frame I and the belt support arm I96, which are adapted to a variety of positional relationships, one with the other, so that they may be assembled in onearrangement or another and employed throughout the entire edge treating apparatus. Furthermore, means has herein been provided for the lateral positioning of the edging units according to the Width or length of the glass sheets. Also, the motor frame I95 and support arm I96 are automatically controlled in their axial relation to the carriage I94 in order that the belt 39 will be maintained against the edges of the glass sheet with a desirable degree of abrading pressure. In

the edge treating units C, identified heretofore by the numerals 45 and 46, in Fig. 1, the basic members of the units will be similarly assembled; however, in the units, identified as 49 and 59, on the opposite side of the conveyor 62, the belt support arm I96 will be reversed with respect to its relation to the motor frame I95.

As shown in Figs. 1 and 8, the abrasive grindin belts 39 of the edge treating units identified by the numerals 45, 46, 49 and 59 have been supported and driven on th said units so that they were trained about the pulley I88, disposed above the glass sheet 25, the drive pulley I83 and the idler pulley I9I positioned to support and effect a tautness in particularly the idle run of the belt. The working run 33 of the abrading surfaces of the belts in this particular arrangement are directed in a downward course against the upper longitudinal corner 36 of the glass sheet 25.

Returning now briefly to Figs. 1 and 4, it will be noted that the glass sheet 25 in passing through the first areaway I4 will have the upper longitudinal corner 36 along one side acted upon,

as indicated at 26 in Fig. 4, by the edge treating unit 45 positioned on one or the left side of the As the sheet enters the second areaway M, the upper longitudinal. corner 36 of the opposite side, as indicated at 21 in Fig. 4, will be acted upon by the grinding belt 39 of the second edge treating unit 49 located on the opposite or right side of the apparatus. Since the carriage I94 of the various units is laterally movable along the rail H3, each of said units may be moved inwardly or outwardly to present the belt thereof against the glass sheet 25, according to its length, in this instance, and simultaneously the motor frame I95 may pivot about the vertical axes of the stub shafts MI and I42 according to the influence of the control elements I53 and I54 when the ends of the glass sheet are not substantially at right angles to the sides thereof and also to compensate in part for flexing in the working run of the belt.

As previously set forth, the first and second grinding belts may be furnished with coarse abrading surfaces while the third and fourth belts should be furnished withabrading surfaces of finer abrasive to smooth the rounded corner edges produced by the first grinding belts. Thus, in moving through the third and fourth areaways I4, the glass sheet 25 will be acted upon by the edge treating unit 46 positioned on the '15 same or left side of the apparatus as the first unit 45 and a fourth unit to on the Same or right side as the second unit :5 whereby the edging operation will be repeated along the upper longitudinal corners 36 of sides as indicated at 26 and 27 in Fig. 4.

Continuing its movement through the first section A of the apparatus, the lower longitudinal corners 3'! ofv th sides 26 and 2? of the glass sheets are acted upon. In order to treat these particular corner areas, the edging units are mounted in such a manner as to present their grinding belts 38 along the said lower longitudina-l corners 31 and the assemblage of their structures is altered so that said belts will be carried in a reversed position from that previously described. In Fig. 15, the motor frames I65 of the edging units 52 and 56, therein shown, are inverted so that the stub axle M! will be journaled in, the lower bearing Hit and the stub axle IM- in the upper bearing" I39. It will also be noted that by inverting theframe Itfi, the arm $52 will be positioned between the contro1 elements I53 and [5% thereby replacing. the arm l5! heretofore described in connection with th operation of these control elements. The belt support arms IE6 are now reversed in their mounted position with reference to the, panels 5d of the frames "15. The end yoke I'M of each arm will thus be positioned beneath the glass sheet in reversed location from that of, the edging unit shown immediately to, the right or asshown in Fig. 8.

To suitably support the fifth to eighth edging units, or those identified by the numerals 52, so and 5?, with reference to the glass sheets 25 on the roll conveyor G2, the framework of the section A is increased in height so that. the cradles or carriages [04 of these units will be mounted to best locate the abrasive belts 39 a ainst the lower corner of the glass sheet.

As shcwnin Fig.' 5, this latter portion of the framework is comprised of framing structures, generally designated 2-23, and which include. vertical standards 224 and 225 and horizontally clisposedchannels 2'26 and 22?. An auxiliary standard228. similar to the standard 68, previously described, is also employed. Between the last framing structure 6.3. and. the first structure 223, there is provided a tower 229 for supporting the roll conveyor 62. between said structures and to permit the desired alternatelocation-of the edgin units it-and 5.2-.

For this purpose, the standards 23.0 of. said tower carry a beam 231, similarly mounted as the beams. 13, for supporting the endsof the continuations of the beams (59 to 1'2 inclusive. At the tower 229, the, means, for supporting the pressure rollers M is also altered due to the increased height. of the structures 223. As herein shown, bridging channels 232 are secured to. thestandards 23B, andthe. standards 22 i and 228. cf the framing structures 223 at substantially the same elevation asthe upper channels 86. of the. framing structures 63.. The bars lillthroughout. the latter portion, Qfthe section A will thus besim'ilarly secured to, the channels 232.

The channels 22.! are generally located atthe same elevation as, the beams 53' previously described, and Will Support the longitudinally extending beams is to 12 inclusive. As shownin Fig. 15, these beams, on. which the bearings 81!, 84;. 8.5, 86' and. 86' are mounted, are arranged so as to extend between.th standards. 22a and 228 and to terminate on either side thereof.. The bearings willjtheretore be located on the. beams from a power unit 16 69 to W. inclusive that are similarly and. alternately positioned throughout the framework to form the open areaways The edging units C are supported on the channels 221 by means of rails 233 and are maintained in their vertical positions by rails 23 and 235, carried by the horizontal channel of the framing structures and between which the rollers 523 are located. 'arly to the rails I [3, the rails 233 are pro" ith slotted openings 236 through which ts @353 may be inserted to secure the cradles by the plates $35 against the rails 233. Pro .on is thus made for mounting sun or the grinding elements at one ole throughout the first portion of the framework 6i and at a higher elevation throughout the second portion of the frame- Work.

As a sheet 25 pa" es beyond the last edging unit 5? of the first grinding section A, it received upon the transfer unit moved therefrom laterally so that in pass" through the second edge treating section the upper and lower 1 er and 29' (Fig. 4.) thereof wil be acted upon by the edging units C p Thus, the glass sheet is received trans longitudinal corners of the lo sely between. the ends of the transfer unit E, as 15 shown in Fig. 1, and is removed therefrom in the direction of its longitudinal axis. This unit, which is shown in detail in Figs. 6, l9 and. 25*, corro' ses a framework 238- wherein plurality of rolls 233 and 240 are disposed in superimpos flation and adapted to provide primarily a moving support surface for the glass sheet and a plurality of driven members to carry said sheet out" "rely from the transfer unit E to the second edge treating section B of the apparatus when the sheet is elevated' above the rolls The framework 238 is formed by legs or standard, i arranged in the corners thereof, side channels 2 32 and 2 .3 and transverse or end channels 26s.

The plurality r I 239, which rovide the glass supporting surface, are mounted in spaced relation on regularly spaced shafts which are journaled at th opposite ends in end channels 245-. The shaf 3 are operated in common from the power unit which operates the roll conveyor E2 of the edging section A. More particularly, the shafts are driven by a link belt 248 trained about the sprocket on the last shaft F! of the Section A. The first shaft 2&5 of the unit E has a sprocket Ml (Fig. 19) mounted thereon and" about which the belt 20- 1 is trained. As shown. in Fig. 20, each of the shaft 2435 have sprockets 2 38 and mounted thereon, said sprockets being alternately interconnected in pairs by link belts so that from the first shaft they will be rotatably operated in common. In moving from the last rolls iii of the section A, the. glass sheet J5 will thus be carried. by the power driven rolls into the central area of the transfer unit The plurality of rolis 126i are mounted on regularly spaced shafts 25! arranged transversely to and above the shafts and which are journaled at their opposite ends in. the side panels 2142 of the framework The shafts 253i are provided at one end with sprockets 252v and 253 that are interconnected by link bolts 2%, as shown in Fig. 20,.so as to be operated in common from. atake-off drive indicated at 255 and driven Preferably, the shafts 251' are rotated faster than the lower shafts 245 to produce a quick removal of the glass sheet once it is located centrally in the transfer unit.

As the sheet approaches this central area of the transfer unit E, its leading edge engages a limit switch 251 to actuate an elevating mechanism 258 to lift said sheet from the rolls 239 upwardly against the rolls 249. The frame 259 of the elevating mechanism-258 is interposed between the shafts 245 and 25l and is carried by pivotally mounted arms 26!) pivotally connected at their ends to the sides thereof by stub shafts 29!. The arms 269, as shown in Fig. 19, are supported on shafts 282 carried by brackets 2B3 secured to side channels 243 of the frame 238.

The arms 299 at each end of the frame 259 are interconnected at their lower ends by rods 264 which in turnare interconnected intermediate their ends by a tie rod 285. This tie rod is attached at one end by a link 265 to a clevi 261 threaded onto the end of a piston rod 258 that is actuated by its piston 2659 contained within the cylinder 219. The limit switch 251 is supported on a bridge 21l carried by the side channels 242 and is positioned so that the incoming sheet on the rolls 239 will cause closure of the contacts of said limit switch that is connected in the circuit of an electrically actuated control valve 212 for the cylinder 219.

One side of the control valve 212 is connected to one end of the cylinder 219 by a pipe 213, while the opposite side of the valve communicates with the other end of the cylinder through pipe 214. This valve is of the conventional four-way type so that the supply pipe 215 thereto will be connected to either of the pipes 213 or 214 when the exhaust pipe 216 is connected to the other.

As diagrammatically set forth in Fig. 18, one side of the switch 251 is connected to a source of positive electric energy 211 by a line 218 and to the coil 219 of a solenoid relay switch 289 by a line 26L completing the circuit of said coil to the negative side of the source 282 by the line 283. The contacts of the relay switch are connected to the source of energy 211 and to the negative side of the source 282 in a conventional arrangement to produce reversal of the electrically responsive control valve 212 by lines 284 and 285. The fixed contacts of said switch are arranged in pairs and alternately complete circuits to the valve 212 through said lines 284 and 285 and by means of contactor bars 289 and 281 carried by the armature 289 of the relay 289. Thus, the pair of contacts 289 are normally closed by the contact bar 286 to maintain a circuit by line 299 from the source 211 to line 284 and one side of the valve 212, completing said circuit by line 285 through the pair of contacts 29l, bar 281, and lines 292 and 283 to the negative side 282. The armature 288 is conventionally held in this position by means of a spring 293.

As presently shown, the pressure supply from the pipe 215 is directed through the pipe 213 to the rear end of the cylinder while the pipe 214, connected to the forward end of the cylinder, communicates through the valve with the exhaust pipe 216. The pressure system to the cylinder 21ll-wil1 thus be such'that the elevating mechanism 258 is maintained in its lowermost position while the pairs of contacts 289 and 29l of relay switch 289 are positioned as above described.

When closure of the contacts of the limit switch 251 is effected by the engagement of a glass sheet 25, a circuit will be completed from the positive source 211 by line 218 through contacts of the said switch, and by line 28! to the coil 219 of relay switch 289 and by line 283 to the negative side 292 and consequently the armature 288 will be moved against the spring 293 to remove contactor bars 286 and 281 from the pairs of contacts 289 and 29L Moving in response to the coil 219, the armature 288 will bring said contact bars into circuit closing engagement with pairs of contacts 294 and 295. One side of the contacts 294 is connected by branch line 296 to the negative return line 292, while the opposite side is connected by branch 291 to the valve 212 through line 284. Conversely, one side of the contacts 295 will be con-' nected by branch line 292 to positive branch lead 299 while the opposite side is extended by branch 299 and line 285 to the valve 212. As a consequence thereof, the polarity of the valves electrically actuated portion will be reversed. The valve 212 will now be caused to direct pressure from the supply pipe 215 through the pipe 214 to the forward end of the cylinder, thereby moving the piston rod 258 inwardly and through the interrelated rods 264 and 285, causing the arms 260 to swing so as to raise the frame 259, Si-

multaneously, the rear end of the cylinder 219 are power driven, the sheet will then be moved across the surface afforded by the rolls 391, as shown in Fig. 1'7, and carried outwardly from the transfer unit E to the second edge treating section B.

To maintain the frame 259 elevated until the sheet has been moved from the area of the lower rolls 239, a limit switch 392, carried on a bridge 393 on the frame 238, is closed upon engagement by the glass sheet. Preferably, the limit switch 392 is disposed in the end of the unit E adja-' cent the section B of the apparatus and will be closed by the leading end of the sheet 25 as the same is being carried laterally to its previous.

line of travel. Closure of the contacts of said switch 392 will complete a bridging circuit from the line 218 by line 394 to the line 28l emanating from the switch 251 to hold the coil 219' energized and will continue after opening of the limit switch 251 and until the following end of the sheet 25 approaches the last row of rolls 249. The limit switch 392 may thus be connected to the positive side 211 of the electrical source by line 395 and connected to the line 28I by said line 394 so as to bridge the limit switch 251 and retain the valve 212 in its reversed position.

When, however, the contacts of the limit switch 392 open, the bridge circuit through line,

394 to coil 219 of the relay switch 289 will be discontinued. The coil 219 wil1 now become de-. energized and the spring 293 will retract the armature 288 so that the circuit of the pairs of contacts 294 and 295 will be opened and the cirouits through the source 211, line 299, pair of contacts 289 and line 284 to the valve will again;

be established by contactor bars 286 and 281; completing the same by line 285, pair of contacts 29f and lines 292 and 283 to the mega- The valve 212 will thus be re-. versed immediately upon departure ofa sheet:

tive side 282.

of glass from the transfer section E so that the supply pipe 215 will again be connected by the pipe 273 to the rear end of the cylinder 2T0, causing the arms 265] to lower the frame 259 thereby displacing the rolls Edi from their elevated, glass supporting position. The transfer section E will now be in condition to receive a subsequent sheet from the edge treating section A.

The second edge treating section B of the apparatus, as shown in Figs. 21 and 22, is substantially a duplication of the first section A. However, as shown in Fig. 23, the supporting surface of the roll conveyor 3% as provided by a plurality of rolls, is considerably narrower than the roll conveyor 62, since the glass sheet 25 is now being moved with its longer dimension extending in the direction of the longitudinal axis of the section G. The rolls 388, 398 and 3H] of the conveyor 3% in the open areaways 3H are provided in short and intermediate lengths to suit the edging section B, as previously described in conjunction with the rolls 8!, 82 and 83. Between the open areaways 3| I, the glass sheet is similarly supported on full length rolls (H2. The shafts 3i3 of the rolls 3%, 399 and are are journaled at one end thereof in bearings 3H5 and 3E5, while the shafts of the rolls 312 are journaled in bearings 3I5 at their opposite ends. The bearings 3M and Bit are mounted, as previously described in connection with the bearings 84, 85, 86 and 86, in alternate order on the beams 69, I0, H and if: according to the open areaways 3H, and the bearings 316 are mounted on the beams 69 and '52, N2 are driven in common from the power unit 3H through link belts 3H3 trained about sprockets 3l9 secured on their related shafts.

In this section, the edging units C are supported substantially as previously described in connection with the first section A; namely, and as shown in Fig. 21, in connection with the first four units C, the support arms N36 for the grinding belts 3t are disposed so that their end yokes I14 are positioned above the sheet of glass, while L in the second four grinding units C said end yokes I'M of the arms Hi5 are located beneath the sheet 25. The abrasive belts 3B of these units will accordingly act first upon the upper longitudinal corners 3E5 of the longer sides as indicated at 23 and 29 in Fig. 4, and subsequent- 1y on the lower longitudinal corners indicated therein at 31.

In actual production, an edge treating or seaming apparatus, of the character herein described, has proven very efiicient and the glass sheets, acted upon, are satisfactorily finished for subsequent operations. While the edge corners are not ground in the ordinary meaning to have a smooth surface as provided by the usual grinding Wheels, the corners are suitably rounded and smoothed off for use of the glass sheets in enclosed areas where said sheets are installed in or covered by framing panels. This apparatus may therefore be used advantageously to prepare glass sheets of rather large dimension and/or irregular pattern such as are ultimately installed as front or rear vehicle windows; the glass sheet bein adapted for tempering, or otherwise suitably treated to be included as a type of laminated safety glass.

The glass sheets, as received from pattern cutting tables, are placed on the loading conveyor D and sequentially moved into the first edging section A of the edge treatingapparatus. Due

The rolls 368, 369, am and 20 to the novel construction of the edging units C) the upper longitudinal corners are alternately acted upon by the grinding belts 30 carried there on. By changing the related positions of the parts of the edging units C; namely, the motor frame I05 and the support arm I06 with reference to the carrier cradle I04, said unit is adapted to operate on the upper and lower corners of one side or the other of the glass sheet with equal facility. In instances of irregular pattern shape wherein the'ends of the glass sheet are disposed at an angle, other than a right angle to the sides of the sheet, the mode of supporting the edge treating units permits them to present the abrasive surface of the grinding belts against these end surfaces so that said belts will flex laterally and follow the glass when the angular line thereof would normally move out of contact with the belt. Reaching the end of the first edge treating section A, the sheets are caused to move transversely so that their remaining sides are presented to the edge treating units. As herein described, the glass sheets may be transferred between the sections of the apparatus by changing the direction of their movement or each sheet may be simply turned by suitable means and continue in a straight line of movement from the first to the second edge treating section.

In the second section B of the apparatus, the abrasive belts of the edge treating units are initially positioned with reference to the approaching glass sheet so as to engage the same in its leading corner areas, as indicated at 39 in Fig. 3, and then to follow the longitudinal side contours to the rear corner areas. The edge treating units will thus automatically present the abrasive surfaces in a manner as to begin at and practically overlap the corner areas finished by the grinding elements of the first section of the apparatus. At the end of the second edge treating section, the glass sheets will be received on the conveyer F for further processing in satisfactory condition of edge finish.

Preferably, although not shown, the edge treating units of each section of the apparatus are located in suitable enclosures to prevent the resulting waste particles of both the glass and the abrasive belts from scattering into the surrounding areas and creating an objectionably contaminated air or surface condition.

It is to be understood that the form of the invention herewith shown and described is to be taken as a preferred embodiment of the same,

but that various changes in the shape, size and arrangement of parts may be resorted to without departing from the spirit of the invention or the scope of the subjoined claims.

I claim:

1. In apparatus for treating the edges of sheets or plates, means for conveying a sheet to be edge treated along a predetermined path, a flexible endless belt having a normally fiat straight working run provided with an abrasive surface and positioned in and at one side of the path of travel of said sheet with the length of said run lying in a plane at an angle to the plane of said path of travel and the width of said run lying normally diagonally of said path and with its abrasive surface at an acute angle to said side of said path in the plane thereof, a pair'of spaced pulleys over which said belt is trained to support-the same, and means for rotating one of said'pulleys to drive the belt. 

